Since paper boards are lightweight and have excellent heat insulating and soundproofing properties, they have been utilized in a wide variety of applications, such as wrapping materials and core materials of furniture. Such a paper board structure has various strengths, such as anti-compression strength in the direction of board thickness, tensile strength, and flexural strength, which are enhanced by sandwiching a reinforcement core, such as a honeycomb core, inside with two paper layers.
In recent years, utilization of paper, which is a recyclable material that can reproduce raw material, has drawn significant attention as a measure to tackling environmental tissues. In particular, replacement of non-paper boards, such as Styrofoam boards, plastic boards, and wood boards, which are currently in use, with recyclable paper boards, if materialized, could be a major positive contributor to tackle environmental issues.
In particular, wood pallets and plastic pallets have been used for freight loading. However, it is difficult to recycle or dispose of wood pallets and plastic pallets. When freight loaded onto pallets is transported, disposal of pallets that are no longer needed at the destination of transportation would be costly, such that pallets are even returned in some cases.
In this regard, paper pallets have been proposed, which would be much more readily disposable, recyclable, and cheaper compared to wood or plastic. Paper pallets can be readily disposed of, compared to wood or plastic, by recycling or incinerating. Paper pallets can also be manufactured at a low cost using recycled paper.
Four-way pallets as shown in Patent Literature 1 are known as paper pallets. Patent literature 1 discloses a four-way pallet comprised of a top board, legs for forming a space for inserting a forklift arm, and a lower board for reinforcing the legs. However, pallets comprising a lower board, as shown in Patent Literature 1, cannot be carried by a hand jack with a wheel on the lower portion near the arm tip. This is because the lower board does not have a space to allow a wheel on the lower portion of a hand jack arm to project out downward.
In this regard, Patent Literature 2 discloses a pallet with an aperture formed on the lower board to allow a wheel provided on the lower portion of a hand jack arm to project out downward. In this manner, conventional four-way paper pallets that can be used with a forklift or a hand jack are characterized by having an aperture formed on the lower board, which has almost the same size as the top board (see FIG. 1B).